Reinforcing concrete patch



.Aug. 30, 1938. L. s. WER-rz REINFORCING cNoRETE PATCH Filed June 15,1936 ATTORNEYS Patented Aug. 30, 1938 UNITED s 'rATEs PATENT ori-ICELouis s. wem, rshaker Heights, om

Application June 15, 1936, Serial No. 85,236

This invention relates to the restoration of concrete structures and hasparticular reference 12 Claims.

to the reinforcing of a concret-e patch. In concrete construction,whether in new work or in the restoring of old structures, it isdesirable to provide reinforcement within the structure to Awith-- standtensile stresses.

in the structure.

This is usually done by an arrangement of steel rods or wires embeddedIn order that these reinforcing members be enicient they should take upany tension to which the concrete in which they are embedded may besubjected. Where a concrete patch has been applied to a concretestructure, tensile stresses, such as induced by temperature changes, areapt to cause cracks or fissures in the patch and particularly in thebond between the new and old concrete. It is, therefore, an object ofthis invention to provide a method of reinforcing .concrete used in therestoration of structures so that the new concrete will be relieved ofsubstantially al1 tensile stresses and to avoid as'far as possible, theformation of such cracks.

Another object of this invention is to provide a method of reinforcingconcrete used in the restoration of structures which will minimize voidsor spaces between the new concrete and the old structure.

Another object is to prvide an improved anchor to be used in reinforcingreplacement concrete and which may be used independently and which willtake the tensile stresses between the new and old concrete.

A further object of the invention is to provide a method of reinforcingreplacement concrete so that in addition to the bond afforded betweenthe two concretes, it will be adequately anchored to the old structure.

ity not completely filled;`

Fig. 2 is a section on the line 2--2 of Fig. 1; Fig. 3 is a detail insection showing the manner in which the anchors are secured in thestructure Fig. 4 is aperspective of a portion of an anchor showing themanner of connecting the reinforcing network thereto; and

Fig. 5 is a perspective of an i ing anchor.

mproved reinforc- Referring to the drawing by numerals of reference, itwill be seen that the invention comprises a tensioned network I0 whichmay be formed of any suitable material having adequate tensileproperties, such as steel, preferably in the form of wire.

In restoring concrete structures it is preferable to rst chip away theloose scale and disintegrated portions of the structure, so that thesurface Il of the old structure adjoining the cavity to be filled willbe firm and hard. In order that the marginal portions of the patch willnot be tapered to a thin or feather edge, it is desirable to removesuflcient of the old structure so that around the marginal portion orcontour of thel region to be patched there is room for a substantialdepth of new concrete. When one or more portions of the cavity to benlled with new concrete are of considerable depth such as indicated at23, it is preferable to employ anchoring devices 21 of improved design,shown in perspective in Fig. 5. They comprise a body portion formed withan upset end 28 provided with an expansion collar 29, and an expandingwedge 30. The opposite end of the body portion is formed into a loop 3|.Crossarms 33 and 34 have a centrai portion positioned in and have theirends I extending radially from the aperture of the loop 3 I. In somecases it may be desirable to weld the crossarms 33 and 34 in the loop3l. These anchors or reinforcing trees. having an elongated bodyportion, are placed in the deep cavity portion 25 at suitably spacedintervals, such for example as a distance between centers of four timesthe height of the individual reinforcing anchors. With the secondaryreinforcing anchors in position, new concrete is applied to the oldconcrete in the deep portions 25 of the cavity so that the secondaryanchors are substantially embedded therein and serve to hold the newcon- '40 crete in position While it is setting, as well as at one end ofthe shank I6, and the opposite end 'serving to reinforce the structureafter the new out of the expansion head I8, when the latterll I'I isprovided with any suitable means to hold it within a recess formed inthe'concrete, such as.

the upset end I1, which prevents its being pulled at suitable spacedintervals. These intermediate anchor bolts engage the network III,preferably at an intersection of individual wires 22, and thereby serveto prevent deflection of the reinforcing network III and tie in theentire mass of replacement concrete Il to the old concrete I2.

The reinforcing network I comprises a number of individual rods or wires22 which may be suitably secured together at their intersections such asby spot welding to prevent relative movement and to more effectivelyreinforce the new concrete. I'his network is formed to approximate theshape of the cavity to be filled. The tensioning of the network ispreferably accomplished by means of tie-wires 26 which are looped aboutthe wire retaining hook II of the tension anchors and about anindividual wire 22 of an adjacent portion of the reinforcing networkIII. When the network is thus suspended in the cavity the tire-wires 28may be twisted by means of a suitable implement such as a nail insertedin the loop of the tie-wire, or otherwise tensioned to hold the networktightly in place. 'I'he reinforcing network Ill may be tied in orotherwise secured to the anchoringv devices or reinforcing trees bysuitable short lengths of wire to firmly bind the new masonry orconcrete I3 to the old masonry or concrete I2. When the crossarms Il and24 are not welded in the apertures of the loopr Il they may be held inplace in any other suitable manner as by passing the wire 35 around thevertical angles formed by their intersection. The reinforcing trees,while affording a strong connection between the old masonry I2 and newmasonry I3, do not interfere with the filling of the cavity 25 andafforded ample space for the cement to enter all the interstices of theold concrete. l

After the reinforcing network I0 has been tensioned between theanchoring devices, the remainder of the cavity is filled with concreteso that the reinforcing network and anchors are embedded therein.However, if the patch or area to be reconstructed is of such a nature`that the concrete may be readily applied through the reinforcinglatticework and around the reinforcing and anchoring trees, the fillingof the cavity with concrete may be done in one operation after all thereinforcing elements have been placed in position,'instead of applyingit in two operations as mentioned above. Also, in patches of the typewhere there are relatively few or no deep porf tions, so that relativelyfew, if any, reinforcing trees are used, and the tensioned network I0 isemployed to furnish substantially the entire reinforcement for theconcrete, the concrete may be applied in one operation.

The present invention provides a method for reinforcing replacementconcrete to be used in repairing masonry whichl distributes tensilestresses such as may be induced by temperature changes acrosssubstantially the entire patch, which tensile stresses may be taken .upby the re- `ama-iso l inforcing network and the old masonry structure.Also, the installation of the reinforcing wire network with an originaltensile stress enables it to function from the time of its installation,and it is unnecessary for the concrete to -be first subjected toexcessive stresses before the reinforcing network will function.Furthermore, reinforcing trees have been provided which are complete"'units individually and serve to firmly bond the new masonry to the old.l

The method which has been shown and de4v scribed is capable of numerousmodifications in A order to carry out the invention in connection withthe reinforcing of concrete or other masonry in various tnies ofreplacement work.

Although I have shown and described but a single application of myinvention in reinforcing a concrete patch, it isV to be understood thatmany modincations are within the scope of the invention and intended tobe included in the` following claims.

What claim is: l A l. The method of reconstructing concrete, comprisingthe steps of preparing the old concrete,

marginal portion of the region to be patched, af-

ilxing to the old concrete a plurality of anchoring means within saidmarginal portion for retaining a reinforcing network, securing areinforcing network to the anchoring means below and adjacent to thenormal surface of the concrete structure, and tensioning the reinforcingnetwork throughout the region to be patched.

3. The method of reconstructing concrete comprising, vremoving thedisintegrated portions of the old structure within the area to bereconstructed, aillxing a plurality of independent concrete anchoringmeans within the deeper por-l tions of said area, tensioning onadditional anchoring -means within said area a reinforcing network overthe area adjacent but below the normal surface of the concrete beingreconstructed and applying the new concrete.

4. The method of reconstructing concrete comprising the steps ofremoving the disintegrated -portions of the old structure within thearea to be reconstructed, aiflxing a plurality of independent concreteanchoring means within the deeper portions of said area, applying newconcrete to the deeper portions, tensioning a reinforcing network overthe area below the normal surface of the concrete being reconstructed,and applying the remainder of the new concrete.

5. The method of reconstructing concrete comy prising the steps ofremoving the disintegrated 6. The method of reconstructing concretecomprising the steps of removing disintegrated portions of the oldstructure, afxing a plurality of independent concrete supporting anchorswithin the area to be reconstructed, and tensioning anchors adjacent themarginal portions of. said area, applying the portion of the newconcrete to the deeper portions, stretching and tensioning a reinforcingnetwork between the tensioning anchors and applyingl the remainder ofthe new concrete.

l 7. A reinforced concrete patch which comprises tensioning andanchoring means aiiixed to the old structure adjacent the periphery ofthe area to be reconstructed, a reinforcing network stretched betweenthe anchoring means, said network positionedsubstantially close to thesurface of the replacement masonry, and elements of the networkextending directly between the anchoring means whereby said elements aretensioned to transmit stresses directly to the old structure, saidanchoring means having their axes at an angle less than a right angle tothe direction of the stress induced by the reinforcing network, andsecondary anchoring means securing the reinforcing network at spacedintervals to the old structure, said secondary anchoring meanspositioned in the deeper portions o f the cavity being repaired.

8. The method of reconstructing old concrete structures having Ideep andshallow portions to be filled in, comprising the steps of removingdisintegrated portions of the old structure, aiilxing a plurality ofconcrete holding means in the solid portions of the old structure toreinforce the new concrete to be applied in the deeper portions,

securing tensioning anchors around the marginal portion of the area tobe reconstructed, applying a portion of the new concrete to said deeperportions, positioning and tensioning a reinforcing network between saidtensioning anchors, and securing the network to said concrete holdingmeans, and applying the remainder of the new concrete.

9. A reinforced concrete patch, comprising a plurality of anchoringmeans having portions network tensioned between the anchoring means andpositioned near the surface of the replacement concrete, said networkhaving elements extending directly between said anchoring means, andconcrete embedding the reinforcing network.

10. A reinforced concrete patch, comprising a plurality of anchoringmeans having portions thereof embedded in the old concrete a substantialdistance beneath the surface thereof, said anchoring means beingdisposed in the old con'- crete adjacent the marginal portions of thepatch, and having portions for securing a reinforcing network theretodisposed near the surface of the replacement concrete, a reinforcingnetwork tensioned between the anchoring means and positioned near thesurface of the replacement concrete, said network having elementsextending directly between said anchoring means, concrete embedding thereinforcing network, and secondary anchoring means, substantially longerthan the first mentioned anchoring means, disposed in the deep portionsof the patch and provided with crossheads to reinforce and hold thereplacement concrete in the deeper portions of the patch.

11. A reinforced concrete patch, comprising a plurality of anchoringmeans having portions thereof embedded in the old concrete a substantialdistance beneath the surface thereof, said anchoring means beingdisposed in the old concrete adjacent the marginal portions of thepatch, and having portions for securing a reinforcing network theretodisposed near the surface of the replacement concrete, a reinforcingnetwork tensioned between the anchoring means and positioned near thesurface of the replacement concrete, said network having elementsextending directly between said anchoring means. concrete embedding thereinforcing network, and secondary anchoring means, substantially longerthan the first mentioned anchoring means, disposed in the deep portionsof the patch and provided with crossheads to reinforce and hold theVreplacement concrete in the deeper portions of the patch, and means tosecure said tensioned reinforcing network to said secondary anchoringmeans to assist in holding the network against displacement.

12. A reconstructed concrete area having marginal portions and deeperportions, comprising substantially rigid reinforcing means in the deeperportions of the area, anchored to the old concrete, a. reinforcingnetwork disposed below, but adjacent the normal surface of the concretebeing reconstructed, secured to and tensioned between a plurality ofanchoring means embedded in the old concrete around the marginalportions of said area, said network having elements thereof extendingdirectly between the last mentioned anchoring means, and concreteembedding all of said reinforcements.

Lome s. wnn'rz.`

